Envelope-opener



A. O.'BLOMGREN.

ENVELOPE OPENER.

(No Model.)

Patented Dec. 18,1894

INVEN TOR.

WITNESSES:

UNITED STATES PATENT OFFICE.

ANDREW O. BLOMGREN, OF GRANITE FALLS, MINNESOTA.

ENVELOPE-OPENER.

SPECIFICATION forming part of Letters Patent No. 531,017, dated December 18, 1894.

"' Application filed April 20, 1894. Serial No. 508,364. (No model.)

To aZZ whom it may concern: Beit known that I, ANDREW O. BLOMGREN, a citizen of the United States, residing at Granite Falls, in the county of Chippewa and that combines efficiency with durability and I ease of adjustment; and, second, to provide a first-class envelope opener-ofv a very inexpenslve construction. I attain these objects-by the novel construction and arrangement of parts illustrated in the accompanying draw ings, in which- Figure 1, is a perspective view of my envelope opener. Fig. 2, is a rear end elevation of the machine, and Fig. 3, is a sectional view on the line a, a, in Fig. 2.

Referring to the drawings by reference numerals, 1, designates the main frame, bed or bed plate of the machine. It consists of the two flat sidebars 2,'the fiat rear crossbar 3, the box-shaped front portion 4 of which the top 5 serves as a tray or table for placing the letter on in opening its envelope, and the upwardly projecting posts 6 having the lugs 7, all cast in one single piece of iron with the rear edge 8 of the table 5 cast in a chill by which it becomes very hard and lasting as a cutting edge for cutting the ends off of the envelopes.

9 is a cutting frame provided at the outsides of its rear corners with two conical trunnions 19, which are journaled in conical hollows 11 in the inner sides of the posts 6. It is further east with a chilled cutting rib 12, which slopes downward from the middle 13 of the front end of the frame toward both sides of the machine.

1 Directly below and very slightly to the rear of the cutting edge 12 the frame 9 is formed with a guiding face 14, which, as well as the extreme front face of the cutting rib 12 are in the form-of segments with the trunnions 10,

for centers, so as toallow the cutting edge 12, to properly co-act with the cutting edge 8, of the table 5. The cutting frame 9 is further formed with the striking button or cap 15,

which is skeletoned by having openings as 16, so as to save iron. It still further is formed with the pendant or'arm 17, adapted to stop against the block 18, which is secured by a screw 19 to the rear bar 3, of the bed plate and prevented from turning on said screw by having a lug 20 let down into a hollow or hole 21 in the bar 3. In the said bar 3, I provide a small hole or hollow 22, in which I insert the lower end 23, of a fiat bow-shaped spring bar 24, of which the upper end 25, is inserted in the hollow 26, in thestriking button 15.

27 are two adjustment rods located one upon each side of the machine. I v are bent at right angles with the rods, then inserted through the holes 28, in the box portion of the bed plate and bent over upon the inner 'sides of said box (as shown at 29 in Fig. 3). Before the rods are thus secured with their front ends theirv rear ends are screwthreaded, passed through the lugs 7, and provided'with the thumb-nuts 30, of which the annular shoulders 31, bear against the rear sidesof the lugs 7. The hollows 11, which receive the trunnions 10, I preferably give a small central opening as 32, (best shown in the cut-away to the left in Fig. 2). It facilitates the'manufacture and afterward serves as an oil hole for the trunnion.

In building the machine it will be observed that nearly all that has to be done is to cast the bed plate, the cutting frame and the stopping block 18, all about ready to be dropped together. The chilled cutting edges may have to be trued up on an emery wheel. The trunnions may be cast in chills, finished or turned by a special tool, forming them in a few seconds. The spring 24, is merely to be cut off from steel strips of the right dimension. The

hollows for the ends ofthe spring may be made to fit the steel without reducing the ends of it the way shownin the present drawings. The rods 27, are two. pieces of, wire very inexpensive to make and drill'the holes for in the castings, and the two thumbnuts cost but a trifle.

In putting the machine together the rear bed plate bar 3, is sprung by forcing the posts 6, apart until the trunnions 10, of the cutting frame are inserted in their journals in the posts 6. The bar 3, will then spring back again and keep the cutting frame journaled in the posts and the spring in said bar 3, takes up automatically the wear of the trunnions should extensive use of the machine shorten them slightly. Should, however, the bed plate be made from iron too hard or too soft to spring suificiently for the said purpose, a brace rod or bolt like 35, may be passed through holes in the posts 6, and screw-threaded as at 36, in one post while its head 37,

bears against the outer side of the other post and is provided with a slot 38, for a screwdriver to take hold of in turning the rod and thus easily produce and retain the most exact fit of the trunnions in their bearings; and should the chilled cutting edges 12, and 8, wear so as to need to be adjusted toward each other, this may be done by turning the thumbnuts 30, by which the side bars 2, of the bed plate will spring enough to allow even the entire cutting rib 12, to be worn away if that should ever be required, but the chilled cutting ribs have proven to be very little afiected by the cutting of paper. 34, are recesses or stopping shoulders provided upon the bedplate 1 for the stopping shoulders 33, of the cutting frame to stop against or upon, and thus arrest the downward motion of the cutting frame. In order to prevent jarring and noise when said shoulders meet, I insert tightly into a hole in the upper shoulder 33, a cushion as 39, which may be of rubber or other similar material, and may be secured in either the upper or the lower stopping shoulder. 40, are flexible pads of rubber or other soft material inserted into and projecting below cavities in the bottom side of the bed plate for which they serve as legs, and also to guard the disk or table upon which the machine may be placed, from getting scratched up by the bed plate.

In operation the end of the envelope is placed upon the table 5, and pushed against the guiding face 14. A pressure or light blow of the hand is then caused to bear on the top of the button 15, so that the cutting frame 9, swings on its trunnions until the stopping shoulders 33, of the cutting frame meet the shoulders 34, of the bed plate. This swinging of the frame 9, causes the cutting rib 12, to pass down close by the cutting edge 8, of the table 5, and cut off the portion of the envelope inserted between the cutting edges. Such portion may be about one-fiftieth of an inch or less, according to the distance from the edge 8, to the guiding face 14, which distance is so regulated that the machine will do no harm to the contents of any envelope opened by it. When the cap 15 is released from the blow or pressure of the hand the spring 24 raises the cutting frame 9, into its normal position, with the arm 17, stopping against the stopping block 18, and the cutting ribs open for ordinary singleslope of shears.

receiving another envelope. By having the upper cutting edge 12, to commence cutting from both ends and finish cutting in the middle I prevent the envelope from getting swung away from the guide 14, by the force of the shearing of the paper (a tendency well known in all cutting with shears and scissors having a guide). Another advantage gained by the double sloping of the cutting rib is that the motion of the cutting frame is thereby rcduoed about fifty per cent. as compared to the Should it become necessary to sharpen the cutting edges by grinding them, it is not necessary to remove the cutting frame from its journal bearings, but merely to loosen the screw 19, swing to one side the stopping block 18 and the cutting frame 9 may then be swung up and backward so as to get with either of the cutting edges 8 and 12, to a small emery wheel or grinding stone.

I am aware that prior to my present invention envelope openers have been made with a cutting frame and a bed frameor box pivoted together and having co-acting cutting edges or knives. Especially is such construction set up in my application, Serial No. 493,104, filed December 8, 1893, so I do not claim such construction broadly, but

lVhat I claim is-- 1. An envelope opener consisting of a cast bed plate having at its front end a box shaped portion of which the top forms a table with a rearwardly projecting chilled cutting edge as 8, and at its rear corner a pair of posts as 6, with conical journal bearings as 11; the cutting frame 9, having the conical trunnions 10, inserted in said bearings in the posts and retained therein by the spring action of the bed plate, and its front end formed with a chilled cutting edge or rib adapted to co-act with the cutting edge 8, of the bed plate, and the guiding face 14, formed below and slightly back from the face of the cutting rib, said cutting rib 12, and face 14, being of a segmental curvature with the trunnions of the cutting frame for center of the segments, apress or striking button as- 15 for operating the cutter frame, stops regulating its stroke and a suitable spring for returning it to its normal position and means for taking up the wear of the cutting edges and the trunnions, substantially as shown and described.

2. In an envelope opener the combination with the spring actuated cutting frame 9, having the hand press button 15, the cutting rib 12, the envelope guiding face 14, and conical trunnions 10, of the bed plate 1, having the cutting edge 8, the holes 28, the posts 6, with the lugs 7, and conical journal bearings 11, adapted to be sprung upon the trunnions, said bed plate having the flexible framebars 2 and 3, the adjustment rods 27, having the thumbnuts 30; and the adjustment rod or screw 35, adapted to take up the wear of the parts of the machine, substantially as shown and described and for the purpose set forth.

3. In an envelope opener, the combination of the bed plate or frame 1, having the feet or cushions 40, secured in and projecting below its bottom side, the cutting edge 8, shoulders 34:, and posts 6; with the cutting frame 9, pivotally secured in said posts and having the striking button 15,a cutting rib co-acting with the cutting edgev of the bedplate, the shoulders 33, having the elastic cushions 39, adapted to meet the shoulders 34:, of the bed plate, the arm 17, and removable stopping block 18, engaging with said arm, the bow-shaped spring 24, acting betweenthe rear frame bar 3, and the front of the inner side of the striking button, sub- 1 5 stantially as and for the purpose set forth.

In testimony whereof I affix my signature in presence of two witnesses.

7 ANDREW O. BLOMGREN. Witnesses:

A. M. OARLsEN, A. P. CROONQUIST. 

